Recording device



' Feb. 14, 192s.

H. L. HOFFMANN RECORDING DEVI CE 2 Sheets-Sheet l Feb. 14, '1928.

H'. L. HOFFMANN RECORDING DEVICE ts-Sheet 2 v Af/y Patented Feb.' 14, 192s.

UNITED STATES PATENT oFFIcE.

HENRY L. HUFFMANN, F EAST ORANGE, NEW JERSEY, ASSIGNOR TO WESTERN ELEC- TRIC COMEANY, INCORPORATED, OF NEW YORK, N. Y., A. CORPORATION OF NEW YORK.

RECORDING DEVICE.

Application led August `3,

This invention relates to a recording mechanism and'I more particularly to the adaption of such mechanism for use in a telephone exchange system. l

The object of the invention is to provide a mechanism of this character which shall comprise as small an .amount of apparatus as is consistent with accurate and dependable operation and which is efficient in operation.

A feature of the invention relates to the provision of a recording apparatus including a series of successively operable counting relays, with the -relays of said series arranged for repeated operation responsive to a series of impulses, the number of relays responsive in the series varying with progressive operations of the series of relays i whereby comparatively large numbers of records of registrations may be taken.

.Another feature relates to an arrangement in which the series of relays comprises a ,number less than the possible number of impulses to be received, each relay on op-' crating, being released atthe beginning of theimpulse which energizes the next relay.

A still further feature relates to the provision of a differential relay associated with the pulsing circuit for preventing the operation of more than a single counting relay on any one impulse. Y

Other features of this invention will be described fully hereinafter and set forth in the appended claims. Referring to the drawing, Figs. 1 and 2 taken in conjunction with each other illustrate so much of a telephone exchange system incorporating a recording mechanism of the type embodying the present invention as is necessary for a complete understanding thereof. Fig. 1 discloses a subscribers line4 terminating in a switch atv the central ollice, other switches for Aextending the line, together with details .of an impulse receiving mechanism responsive to designation im'- pulses for establishing a record of a call at the olce. l Fig. 2 shows in full two separate'relay register devices, each for receiving and, re-

laas. serial No. 855,387.

cording a different portion of a designation. At the right of this figure there are also illustrated in schematic form two additional registers for recording other parts of the designation.

In telephone systems of the automatic and 55 semi-automatic types, it is found desirable to register on apparatus located at the central olice the designation of the wanted line or circuit. This designation having been recorded may later be used for governing the d0 selective operations of switches to extend the required connection or for controlling well-. known call indicating mechanism.

While the applicants invention has for convenience been applied to a particular type of automatic telephone system and in conjunction with relay registers of the type disclosed in the patent to S. B. Villiams Jr., No. 1,530,968, issued March 24, 1925, it is to be understood that it is equally applicable to other types of systems and registers.

In the system disclosed the subscribers line 100 extends to the central otlice and there terminates in a line switch 102 diagrammatically shown. adapted to extend thesubscriber-s line 100 to any o f a number of trunks, one of which, trunk 104, 105, is illustrated leading to a first selective switch 106. Switch 106 ma be of the same character as the line switc 102 and serves to extend the incoming trunk' 104, 105 to other trunks 142, 143 and 144. Obviously, trunks 142, 143 and 144 may lead to succeeding selective switching devices where they are again selectively connected 35 to other trunks and so on until the connection is completed.

Also located at the central office is an im-v pulse receiving and recording mechanism comprising an organization of relays and circuits, the function of which is to receive series of impulses generated through the op-` eration of the dial of the calling subscribers line and to record the designations represented by such impulses There may be any 95.

desired 'number of these recording mechanisins arranged to serve a group of subscribers lines, the particular one to be taken The line switch 102 is 75V -for use at any given time depending upon its -busy or idle condition A selecting switch 103 is provided for associating an idle one of the recording mechanisms, com rising the remainder of Figs. 1 and 2, with t e` articular trunk 104, 105 to which the calling subscribers line has been extended by the switch 102.

The switches 102, 103 and 106 may be of the general type shown and described in detail in the patent to C. L. Goodrum No. 1,551,024, issued August 25, 1925. On the other hand, these switches may be of any well-known type such as power driven selectors, or switches in which multi-contact relays are employed for building up the connections with means for selecting and operating the necessary relays. While the recording mechanism embodying this invention is well adapted for use in systems employing switches ont the character illustrated, it is to be understood that any other suitable form oit switching device may be used instead.

A detailed description will now be given of the operation of the system. lt will be assumed that the designation which the subscriber wishes to record comprises four digits representing the number 2134i. Each of these digits is represented by a separate series of circuit interruptions over the calling line which are recorded by the counting relay series shown in Fig. 1 and registered successively on the four respective registers 200, 201, 202 and 203. When the calling subscriber initiates the call by'removing his receiver from the switchhook, the line switch 102 operates to extend the calling line to an idle trunk 104, 105. Moreover, the selecting switch 103 operates to associate the idle rccording mechanism shown in detail with the selected trunk 104:, 105. ln response to these operations a circuit is closed from battery through resistance 112 right winding of the impulse relay 111, through the switch 103, conductor 105, through the switch 102, over the loop of the calling line 100 and returning through the switch 102, conductor 104, through the switch 103, left winding of the balancing coil 113 to ground. Relay 111 operates and closes a circuit from ground through its left contact. winding, of relay 115 to'battery. Relay 115 operates and prepares circuits to be described hereinafter. Nothing further happens until the calling subscriber manipulates his dial.

' llVhen the subscriber operates his dial 101 of its circuit. .A circuit is now closed for relay. 116, from battery through this relay, the right contact of re ay 115, to ground at the r1ght contact of relay 111. Rela 116 locks over its inner right armature an contact, the intermediate contact of relay 114, conductor 145 to ground at the inner left contact of relay 115. Another circuit is es'- tablished at this time from ground through the left armature and back contact of relay 111, outer left front contact of relay 115, left winding of relay 119 to battery through the Winding of relay 118 and 4in parallel therewith through the right winding of re'- lay 119, conductor 132, back contact and inner upper armature oi relay 123, back contact and inner upper armature of relay 122, back contact and inner upper armature ot relay 121 to battery through the winding of relay 121. Relays 118 and 121 become energized but relay 119 being differentially wound does not energize at this time. it should be noted in this connection that the armatures and contacts of the counting relays 121 to 125 inclusive', are so designed that the inner lower armature of each of these relays makes connection with its front contact slightly in advance of the time when the remaining armatures disengage their back contacts. Hence. the inner lower armature of relay 121 closes its front contact before the operating circuit of said relay is opened at the inner upper armature and back contact thereof. Relay 121 now locks in a circuit traceable from battery through its winding and its inner lower armature and contact, the lowermost contact of relay 122, conductor 133, the outer contact of relay 114. inner contact of relay 116, intermediate contact of relay 114 to ground on conductor 145. As soon as relay 121 energizes, the circuit through the right hand winding of relay 119 is opened and relay 119 being unbalanced immediately energizes opening the branch of the impulse circuit extending to the counting relays through its right winding and armature and over conductor 132. The energization of relay 119 thus prevents the same closure at the back contact of relay 111 from operating a second relay of the counting relay series. DRelay 119 is now maintained energized over its left winding until relay 111 is again energized at the end of the rstline-circuit interruption, when the circuit through t-he left winding of relay 119 and the winding of relay 118 is opened. Relay 118 being slow to release maintains its armature attracted until the termination of the series-of circuit interruptions.

ln response to the second and last interruption of the series, relay 111 releases, again closing the energizing circuit of relay 118 and establishing a circuit over conductor 132, the inner upper armature and Vback contact of relay 123, the inner upper armature and back contact of relay 123, the inner upper armature and back contact of relay 122, the inner upper armature and front contact of relay 121, winding of relay 122 to battery. Relay 122 upon energizing, breaks its own operating circuit and locks over its inner lower armature and front contact, lowermost armature arid contact of relay 123, thence to ground on conductor 145. At its lowermost armature and contact, relay 122 opens the locking circuit of relay 121, permitting the ylatter relay to release. Thus, at the end of the first series of circuit interruptions, the counting relay 122 is operated and all othercounting relays are unoperated.

During the transmission of the impulses -t-he slow-to-release relay 118 maintains its armature attracted by means of a circuit closed intermittently at the left contact of relay 111. At the 'end ofthe series, however, an interval of time elapses during which the circuit of relay 118 is heldf'open by the relay 111 suiiiciently long to permit `the deenergization of relay 118; Relay 118, on deenergizing, `closes a circuit from ground through the inner left contact of relay 115, conductor 145, contact of relay 118, outer right contact of relay 116, inner contact of relay 114, conductor 134, back contact of relay 204, winding of relay`205 to battery. Relay 205 operates and completes a circuit from battery through its' winding and left contact, conductor 135, winding of relay 114, thence to ground at the inner left contact of relay 115 as described. Relay 114, however,

' does not operate in this circuit since 1t is shunted by the circuit first traced through the winding of relay 205. right contacts extends the control conductors 137, 138, 139, 140 and 141 through to the relays of the first register 200.

Since the counting relay 122 is operated a `circuit may be traced from the grounded conductor 133 through the uppermostv back contact of relay 125, uppermost back contact of relay 124, uppermost front contact of relay 122, conductor 138, next to the inner right contact of relay 205, winding of relay 208 to battery. Inasmuch as none of the remaining counting relays are operated no condition is placed on any of the other vcontrol conductors and hence relay 208 is the only one to be energized in the register set200. Relay 203 attracts its armatures and closes a locking circuit from battery through its ujindingnnd inner lett contact, conductor 145 to `ground. Relay 208 also closes a circuit from battery through the winding of relay 204.v conductor 216, outer left contact of relay 208 to ground over conductor 145. Relay 204 attracts its armatures and opens the shunt around the winding of relay 114. Relay '114 immediately operates in series with the winding of relay 205 by means of the circuit previously described. Relay 114 at its middle Contact opens the holding cir- Relay 205 at its cuit of relay 116 and this latter relay becomes deenergized. Relay 116, in turn, opens the energzing circuit of relays 205 and 114 and they also release their armatures. Relay 114 at its outer contact also opens the holding circuit of counting relay 122 and this relay becomes deenergized. Thus, the counting relays and the receiving circuit in Fig. 1 have completely restored to normal cond'tion at the end of the series of impulses in readiness to receive the next series of impulses. Relay 205, on decncrgizing, disconnects control lea-ds 137, 138, 139, 140 and-141 from the iirst register 200 to prevent interference when the next digit is recorded.

The subscrfber now manipulates the dial 101 to cause a single circuit interruption representing the seconddigit of the designation. As has already been explained, this single interruption causes the lirst counting relay 121 to operate and lock through the back contact of relay 122.- At the end of the series, the slow-to-release relay 118 becomes deenergized and a circuit is closed from ground through the inner left contact of relay 115, conductor 145, Contact of relay 118, outer contact of relay 116, inner contact of relay 114, conductor 134, thence through the right front contact of relay 204, conductor 217, right back contact of relay 212, winding of relay l213 to battery. Relay 213 operates and closes a circuit from battery through its winding and left contact, conductor 135, thence through the winding ot relay 114 to ground as previouslyexplained. Relay 114 does not operate since it is shunted by the energizing circuit of relay 213. Re-

lay 213 at its right contacts extends the control conductors through to the relay registers of the second set 201.

Since the first counting relay -121 alone is operated a circuit is traceable from ground over conduct-or 133, `through the uppermost' back contact of relays 125, 124 and 122, uppermost front contact of relay 121, conductor 137, thence through the innermost right contact of relay 213, Winding of relay 214 to battery. Relay 214 operates and locks in a circuit from battery through its Winding and inner lett contact over conductors 218 andy 21S) to ground over conductor 145. Relay 214 also completes a circuit from battery through the winding of relay 212, conductor 220, outer left contact ot relay. 214 to ground over conductors 218 and 145. Relay 212 operates and locks through its Winding and left contact to ground overy conductor 218 and opens the shunt around the winding of relay 114. Relay 114 now operates in series with relay 213 opening the circuit of relay 116 as explained, which in turn, opens the circuit of relays 114 and 213, these relays becoming deenergized. Also the counting relay 121 and the other relays of the impulse receiving circuit are restored to norlll may represent different numerical groups may be controlled by magnets or relays 108, 109, 110, etc. These magnets are selectable inany suitable manner by circuits controlled by the relays of the registers 200, 201, 202 and 203.

It is furthermore obvious that instead of operating switch magnets, the circuits controlled by the register rela s could be connected to indicator lamps tor directly indicating the digits recorded by the several re isters. i

en kthe last digit has been recorded on the register 203 some element individual to said register such as the relay 223 may operate to close circuits for relays 210 and 215 in an obvious manner. Relay 210 completes a circuit from ground through its contact, right front Contact of register relay 208, innermost right back contact .of register relay 206, next to the innermost right back Acontact of register relay 209 to conductor 227. The conductor 227 may extend `directly or through intermediate controlling devices to select a magnet 108, 109 or 110 representing an outgoing trunk identified by the registration on the register 200.

Similarly, relay 215 completes a circuit from ground through its innermost contact, right back contact of relay 224, right back contact of relay 226, outer right back contact of relay228, outer right front contact of relay 214, thence to conductor 229. The conductor 229 may correspondingly extend to cause the selection of a. trunk at a succeeding switch for further extending the desired call. Also the setting of the registers 202 and 203 correspondingly determine the selections at succeeding switching stages. Inasmuch as this principle of governing the selective operation of switches in accordance with the designations registered on registers is Well knownand since it plays nolimportant part with the subject-matter of the present invention, it is not believed necessary to disclose and describe the same in further detail.

Thus far, only the rst four digits of the numerical series, namely, 1, 2, 3, and 4, have been considered. In order to illustrate the operation of the counting relay series, -a description will now be given or' the manner in which the apparatus :functions in response to series of impulses identifying the remaining six digits. f

Assume, that a series of five impulses is transmitted over conductor v132 by the impulse relay 111. It will be recalled that at the end of a series of four impulses relay 124 is energized and all remaining relays are deenergized. Since relay 124 is locked di` rectly to conductor 133, it does not become unlocked during the subsequent operation of the other counting relays. When the; fifth impulse is transmitted, the circuit over conductor 132 extends through the innermost upper back contact of relay 123, innermost upper back contact of relay 122,`innermost upper back contact of relay 121, Winding of relay 121 to battery. Relay 121 operates, opening itsk own operating circuit and locks in a circuit from battery through its Winding and innermost lower Contact, lowermost front ycontact of relay 124 to the, grounded conductor 133. Since relay 124 is locked directly on conductor 133, relay 121 is therefore locked independently of the subsequent operation of the other counting relays. At

the end of the series when relay 118 becomes deenergized and relay 205, for example, becomes energized to extend the control conductorsv 137, 138, 139, etc. through to the register 200, a clrcuit may be traced from ground over conductor 133, uppermost back Contact of relay 125,uppermost front contact of relay 124, conductor 130, armature y127 and front contact of relay 121, conduc- `tor 140, next to the outer contact of relay 205, winding of relay 209 to battery. Thus, the register relay 209 is operated.

If a series of six circuit interruptions are caused, relay 111 in response to the sixth in.

terruption closes the circuit traced over conductor 132, thence through the inner upper back contacts of relays 123 and 122 in se ries, inner upper front contact of relay 121,

yWinding of relay 122 to battery. Relay 122 is grounded as before to cause the energiza` tion of a register relay, for example 209, and an additional circuit is closed vfrom ground on conductor 133, thence as traced to conductor 130, armature 126 and contact of relay 121, conductor 136, intermediate upper armature and back contact of relay 125, conductor 146, armature 128 and front contact of rela 122, conductor 137, thence to battery throug a. register relay, for example, 206, of the register 200.

If a series of4 sevenycircuit interruptions are caused, relay 111 on deenergization upon the seventh interruption closes a circuit over conductor 13,2, through theinner upper back contact of relay 123, inner upper front contact of relay 122, winding of relay 123 to battery. Relay 123 operates, opening its own operating circuit and locks over its innerlower Contact, the lowermost contact of relay 121 and the lowermost back contact of relay to grounded conductor 133. At its lowermost Contact, relay 123 also opens the holding circuit of relay 122 and relay 122 deenergizes. Thus, at the end of the seventh circuit interruption, relay 121, 123 and 121 are energized. As previously described, relays 121 and 124 jointly associate grounded conductor 133 with conductor 140, thereby causing the energization ot' a register relay, for example, relay 209. A circuit .is also closed at this time from the grounded conductor 133, uppermost back contact of relay 125, armature 129 and front contact of relay 123, over conductor 138, causing the energization of a register relay such as 203.

If a series of eight circuit interruptions result fromthe dialling of the digit 8, relay 111 uion deenergizing the first seven times, esta lishes circuits for operating the counting relays as heretofore described for the digit 7. Upon the eighth interruption a circuit is closed over conductor 132, the inner upper armatures and front contact of relays 123 and 124, the inner upper armature and back Contact ot' relay 1 25, winding of relay 125 to battery. Relay 125 operates, opening itsxown operating circuit and locks over its inner lower contact directly to conductor 133. Atits lowermost armature and back contact relay 125 also opens the holding circuit of relay 123. Thus, at the end of the eighth circuit interruption, relays 121, 124 and 125 are energized. A circuit is now completed from grounded conductor 133, over the armature 129 and back contact of relay 123, uppermost front contact of relay 124, conductor 130, armature 127 and front contact of relay 121, thence over conductor for operating a register relay, for example relay 209. A circuit is also closed from conductor 133 over the uppermost front contact of relay 125, conductor 147, armature 128 and back contact of relay 122, conductor 137, thence through a register relay', such as relay 206. A third circuit is closed from conductor 133, armature 129 and back Contact of relay 123, uppermost front contact of relay 124, conductor130, armature 126 and contact of relay 121, conductor 136, intermediate upper armature and front contact of relay 125, armature 117 and back contact of relay 122 over conductor 138 for operating a relay such as 208. Thus, register relays 206, 208 and 209 are operated at the end of the eighth circuit interruption.

Should the subscriber dial the digit 9, relay 11 functions as above described 1n response to the irst eight circuit interruptions and in response to the ninth interruption with relays 121, 124 and 125 operated, closes a circuit over conductor 132, the inner upper armatures and back contacts of relays 123 and 122, the inner upper armature and front contact of relay 121 to battery, through the winding of relay 122. Relay 122 operates` opening its own operating circuit and locks over its inner lower front contact and the lowermost front contact of rela 125 to ground over conductor 133. At t e end of rthe ninth circuit interruption, counting relays 121, 124 and 125 are thus operated. lVith relays 121, and 124 operated, conductor 140 is grounded as previously described a-nd register relay 209 is operated. In addition, a circuit is closed from grounded conductor 133, armature 129, and back Contact ot' relay 123, uppermost armature and iront contact oi' relay 124, conductor 130, armature 126 and Contact of relay 121, conductor 136, intermediate upper armature. and front contact of relay 125, armature 117 and front contact of relay 122 to conductor 139, thence, through the Winding of a register relay such as 207. Thus, register relays 207, and 209 are operated.

Lastly, in response to the dialling of the digit 10, relay 111 functions as above described in response to the first nine circuit interruptions and in response to the tenth interruption with relays 121, 122, 124and 125 operated, a circuit is completed over conductor 132, the inner upper back contact of relay 123, the inner upper front Contact of relay 122 to battery through the winding of relay 123. Relay 123, upon operating opens its own operating circuit, and locks over its inner lower front contact, the lowermost front contact ot relay 122, t0 ground on conductor 133. With all of the counting relays operated, a circuit is established from ground on conductor 133, the uppermost front contact of relay 125, conductor 147, armature 120 and contact of relay 123, intermediate upper armature and front contact of relay 124, conductor 141, outer right contact of relay 205 to battery through relay 211. If the digit 10 is dialled as a second or subsequent digit of a line designation, no register relays are operated, but the transfer relay of the particular register, such as relay 212 is operated directly over conductor 141.

It frequently happens that the calling subscriber in attempting to initiate a call causes a preliminary impulse to be sent to the oice accidentally. This impulse, if recorded on the register 200 would mutilate the call and prevent the subscriber from obtaining the proper connection. Accordingly, means are provided for eliminating a first impulse when received at the central oiee. Assume that in initiating a call the subscriber accidentally sends a single impulse. This impulse is received and causes the operation of the first counting relay 121. After an interval the slow relay 118 becomes deenergized and the circuit of relay 205 is closed as hereinbefore explained. With relay 121 operated a cirmasses cuit is completed from ground over conductor 133, uppermost back contact of relay 125, uppermost back contact of relay 124, uppermost back contact of relay 122, uppermost front contact of relay 121, conductor 137, 1nnerlnost right front contact of relay 205, winding of relay 206 to battery. Relay 206 operates and closes a circuit from battery through the winding of relay 204, left contact of relay 206, thence through inner right contact of relay 205 to round over conductor 137 as traced. It will be notedthat relay 206 cannot close a. locking circuit for itself as is the case of the remaining relays 208, 207 and 209. Immediately that relay 204 operates it removes the shunt from around the winding of relay 114. Relay 114 operates to open the circuit of relay 116,

i which in turn yopens the circuit of relays 114 and 205. Immediately that relayl 205 releases it opens the circuit of relay 206, which in turn opens the circuit of relay 204. Hence, for a single preliminary impulse, register 200 is immediately restored to its normal position so that when the first and regular series of impulses are transmitted, arecord of the same may be placed on the register 200 in the proper manner.

When the recording mechanism is no longer required the circuit of relay 111 is opened in any well-known manner causing in turn `the release of slow relay 115 and the removal of ground from conductor 145. The removal oi' ground from conductor 145 and consequently from its branch'conductors 218 and 219 destroys the holding circuits for the various register relays such as 208, 203, 228, 214, etc. which are in operated condition at the termination of a series of pulses. All relays of the recording mechanisnrare thereupon released.

` The following chart shows the lmanner in which the counting relays are operated either singly or in combination to record the impulses transmitted in accordance with the ten numerical digits, and the combinations of control conductors which are grounded by the relays.

Digit Counting relays operated Convtgggetors a 124v 137 13s s 121 124 -140 p a 121 122 124 137 14o l7 121 12s 124 13a 14o s 121 124 125 1a? 138 14o trolled b ing said What is claimed is:

1. In combination, an impulse circuit, a

the maximum number of impulses in any series to be transmitted over said circuit, means lncludmg contacts of each of said relays for extending said impulse circuit to said relays in succession and repeatedly, means to transmit impulses over said circuit to energize said relays, means for deenergizing a previously energized relay at the beginning of the impulse energizing the next relay, and means for varying the number of relays in said series responsive to impulses with progressive operations of said series of relays.

3. In combination, an impulse circuit, a single series of relays less in number than the maximum number of impulses in any series to be transmitted over said circuit,

means including contacts of each of said relays :Eor extending said impulse circuit to said relays in succession and repeatedly, means to transmit impulses over said circuit to energize said relays, means for deenergizing certain previously energized relays at the beginning of the impulses energizing the next relays, and means for holding certain of said relays operated until the completion of the series ofimpulses whereby the number of relays in said series responsive to impulses is diminished with progressive operations of said series of relays. l

4. In combination, a series of relays,

means for interconnecting said relays whereby they operate successively in response to a series of impulses, a branched impulse circuit, said relays having means for extending one branch of said circuit successively thereto, a diierential relay having a winding in each of said branches, means for opening said one branch of said circuit upon the operation of one of said series of relays in response to an impulse whereby said diierential relay is operated, and means consaid differential relay for hold- Y ranch open until the termination of the impulse.

5. In combination, a series of relays,

means for interconnecting said relays whereby they operate successively in response to a series of impulses, a branched impulse cirfor opening said branch whereby the operation of more than one of the series of relays in response to a single impulse is prevented. l0 In witness Whereo'f, I hereunto subscribe my nume this 27 day of July, A. D., 1923.

HENRY L. HOFFMANN. 

